- How To Hints
- Indoor Unit
- Station List
- Transmitter Specs
- Multiple Transmitters
Please keep in mind that this information just the authors opinion.
Thanks for writing and greetings from ?. I will answer your questions in
the order that you asked them:
My first question is this more of a hobby or can you run ads and make a profit?
Most people run the stations as a hobby (non-profit). However their is no reason that
you couldn't make a profit if you wanted to. However in order to make a profit you
will have to have a good coverage area. That means a sizeable investment in equip-
ment. For example each transmitter will cover about a 2 mile radius if it is mounted
at least 30 feet high. To gain another 2 mile radius you will need another transmitter.
So you keep adding transmitters until you get the coverage area you want. Each
transmitter can range in price from $300.00 each to well over $1,000 each. I would
personally recommend that you use the "AM1000 Rangemaster". You can visit their
website at: http://www.am1000rangemaster.com (Tell Keith Hamilton that Bill ?
sent you). If you space the transmitters 2 miles apart the carriers will not need to
be synchronized. To get the audio to the transmitters you can use a telephone link
"broadcast loop" or you could link the source audio to each transmitter using Part15
STL (Station-Transmitter-Link). 10 transmitters would cover about a an 8 mile
radius with a fairly strong signal (mounted at least 30 feet high). I am sure if you
decided to order 10 transmitters that Keith might consider giving you a discount
for a volume purchase. Another considerable cost would be your studio or
automation equipment if you choose to go automated.
My low power AM Station (?????????????) is totally automated with a database of
over 6000 songs. I have approximately 15K invested in XJO but you can pay allot
less if you purchase used equipment.
Also, what is your listening range? How many miles?
???'s primary daytime primary coverage area is a 5 mile radius from my home. The
secondary coverage area is 5-7 mile radius. The absolute limit of the station is 10
miles. Why do I get almost triple the range of a standard single transmitter? First I
live on the top of a small hill (elev 1400 ft). Secondly my transmitter is mounted at
the top of my Ham Radio Tower at a height of 70 feet. The coverage area will change
depending upon terrain.
Any other advice you could provide would be greatly appreciated.
Stay away from Part 15 FM. Unless you have a Professional Engineer come out and
verify that you meet the "field strength limits" for Part15 FM operation ... you will
be busted. Part 15 FM is absolutely worthless in my opinion. If you meet the field
strength limit you might get 250 feet out of your transmitter. People buy a Part 15
FM transmitter set the power to a low level then get on. All of these people get
busted ... just read the enforcement division activities listed on http:www.fcc.gov
The FCC aggressively enforces Part 15 FM ... making a mistake on Part 15 FM will
cost you at least 10K in fines and maybe the confiscation of your gear.
FCC Part 15 AM operation is the way to go. The FCC does not restrict the range of
your station based upon a "field strength reading". You are restricted to 100mw of
output power with an antenna ... feedline ... and or ground not to exceed 3 meters
in total length. This is why allot of Part 15 AM transmitters are remotely mounted
at the top of poles and towers. Another loop-hole in the Part 15 rules and regulations
is that the FCC does not define what a "ground is". If you mount your transmitter on
a 30 foot mast pipe (grounding the transmitter to the mast pipe) with the mast pipe
itself being earth grounded ... doesn't the mast pipe serve as your ground? Another
situation is that if you installed a Part 15 AM transmitter at the top of a multi-floor
building (grounding the transmitter to the building electrical ground on the roof)
Isn't the building electrical ground in fact GROUND even though you are mounted
on the roof? The FCC can of course do anything they want as they hold all the
cards. it is not mandatory I would suggest that you only use a FCC Part 15 approved
transmitter. If the FCC visits you they will know exactly what they are dealing with
and what the capabilities of the transmitter are. The bottom line is that YOU are
responsible for your station no matter what anybody else says.
Stay out of trouble with the FCC. Most likely the FCC will never pay you a visit
unless someone reports you (complains about your station). These complaints
can come from a local Radio Station or your neighbors. If someone reports you
the FCC will certainly pay you a visit. You can play almost anything but be advised
that if you transmit "Religious" or "Political" material you might anger your neighbors.
Also playing music that contains foul language would definitely be a problem. Don't
knowingly run over the 100mw power limit.
When I put my Part 15 AM station on the air I wrote the FCC an eight page letter.
I told them who I was ... what I was doing ... why the station was legal ... and
when I was putting it on the air. I also sent the pictures of how my transmitter was
installed. I also told them that I have an "extra class" Amateur Radio License (KJ6EO)
so they know who I am and how to reach me. I told them they were welcome to
come out and visit me anytime. They emailed me and said they would forward my
letter to their LA Field Office ... and if they had any concerns they would come out
to see me. I have been on the air for 2 years and I have never been visited.
I am certainly "not an authority" on Part 15 AM Radio. There are others that are
much more qualified than myself to speak on the subject. However if you are
serious about getting on the air ... I am sure I could give you some advice on
how to set your station up at a minimal cost.
So for what it is worth ... the above is my comments on the subject. Feel free to
write back ... I could be glad to answer any questions you might have.
P.S You can play my station via the internet if you have Winamp or Windows
Media Player 9.0 installed. Here are my broadcast URLS:
Hello,I am trying to find out more information about part 15 low-powered Am radio stations. My first question is this more of a hobby or can you run ads and make a profit? Also, what is your listening range? How many miles? Any other advice you could provide would be greatly appreciated.Regards,??
Hi ???? -
Good to hear from you (>: Let me answer your questions in the order that
you ask them:
Just wanted to make sure I understand a few things. You can add transmitters, but you said you'd want them 2 miles apart from each other. So basically You can't just mount 4 or 5 transmitters at the home base? By spreading them out It then extends the range
Transmitters that are spaced at least 2 miles apart do not need to have their
carriers synchronized. Space them any closer together and the carriers will
heterodyne each other (squeel). Keith Hamilton's AM1000 transmitters can be
synchronized with each other via a cable. Just as a test here at my location I
placed (2) AM1000's 40 feet apart and synchronized them. Adding the second
transmitter doubled the coverage area. These two transmitters were
mounted on tripods sitting on my patio roof (low elevation). I got a 2 mile
primary coverage area with a 2 to 4 mile secondary coverage area. There was
also a noticeable increase in the loudness of the station. You can run multiple
transmitters at the home base if you synchronize them. However I have heard
that the FCC frowns on running several transmitters spaced close together.
They don't seem to have any problem with running multiple transmitters as
long as they are spaced at least the distance of a large shopping mall apart.
NOTE: transmitters can be zero beat together so they won't squeal or rumble
but there will be some phase flutter. Spacing them apart in each other's fringe
will help this. KH
How big are these transmitters?
The AM1000 is mounted inside a weatherproof outdoor enclosure that
measures (8.5" x 4.5" x 3.5"). Visit Keith's website at:
to see pictures of the AM1000. The antenna that Keith suggests is a CB
stainless steel whip (108 inches). I use a Francis 96" fiberglass CB whip on
my transmitter because the fiberglass whip is light weight. You can get one
of these fiberglass whips at any CB shop .. or on the internet.
how difficult is it to gain permission to place them around the area?
This could be a problem. As you can imagine most people would want to
charge you to put a transmitter on their property. If you find a place then
you need to get your audio out there. You also might need a phone line
(broadcast loop) or STL and AC power. If I was going to run multiple
transmitters I would most likely approach the city where I live. I would
offer them something in return for letting me put a transmitter(s) at
city locations. Something like airing their PSA's or City events, etc. If
you put them at businesses then give them some free advertising.
In regards to the automated equipment, Does this mean that you can go in and lay out the content you
wish to have on the radio in advance? (so you're not sitting at the computer selecting each song All day long)
Curious how far in advance you can program.
That is exactly what it means. My automation software (OTSDJ) + Logging
and Scheduling Module is self sustaining. As long as the computer has power
and it doesn't fail for hardware reasons the station would run forever. I have
a 1 hour template for every kind of music I play. That template has around
16 songs in it + PSA's + transitions + shotguns + etc. My scheduler script
calls up whatever template that I choose each hour. So for a complete day
of programming you will have 24 entries in your scheduler telling it which
template to call up each hour. I generate my hourly blocks 48 minutes in
advance before they air. My scheduling script has been written for a complete
week (7-Days). When the scheduler gets to the end of the script it just rolls
over and starts at the beginning.
Finally, I'm just curious if anyone does talk radio? through part 15 am? Can these stations become affiliated
with radio shows? etc? I'm talking of Nation wide radio shows!
I have heard of some Part15 talk stations. You would need to do a search on
the internet to look for those stations. There are several sites that have lists
of Part15 Radio stations. I seriously doubt that any established Nation Wide
Radio Show would be interested in broadcasting via Part15. They have 50Kw
stations ... why would they be interested in 100 milliwatts? I am not saying a
Nation Wide Part15 show couldn't happen. However in my opinion the show
would have to be started within the Part15 Radio Station network. All of the
stations could download the show from the internet. Then all of them could
air it at the same time. There is already an attempt being made at doing
something like this. It is the "Daddy G" Oldies Radio Show ... allot of Part15
stations are carrying it.
Basically I have 3 areas i'm thinking of. Of course i'd only start with one and see how it goes. The first
one is an Island, so I think as far as coverage I could get the most with fewer transmitters then the other
areas. I was looking to play some talk radio shows, then have music during times also. Or complete talk,
not quite sure. But would something like this work? under the part 15 am station??
The good thing about a Part15 Radio Station is that you can do basically
anything you want. You do have to remember though that you cannot air
unacceptable material (this is common sense). Regarding talk radio I would
be careful what you say. You would be surprised how pissed off your
neighbors can get when you air opposite views over your Radio Station in
their back yard. I already know of one individual that was literally "Run out
of town" for broadcasting his views. The FCC protects real radio stations
from this type of thing ... but we have no protection.
The reason why i ask all this is because in my area (not the island i talked about before) A guy has been
cleared and still waiting approval from FCC for a low powered radio station. The market is completely
open and he will do real well, my hopes was to have a good station to get some of the listener ship.
Since he will get a lot of people turning on the AM dials.
I would try to make a buddy of this guy. As a friend he might air a small
spot mentioning that "you also" are on the air "your frequency" etc.
THE BOTTOM LINE:
Running a profitable Part15 AM Radio Station would be a very difficult thing
to do. We just don't have the coverage area for it. Also our signals are
weak and just about any interference will take us out. People get tired of
listening to all the interference while they are trying to listen to our content.
In my opinion Part15 Radio is basically "a toy" for those who want to do their
own broadcasting. I do it just for the fun of it. Real Radio Stations make
their revenue from advertising. If I was going to pay for advertising my first
question would be "how large is your coverage area".
However ... anything can happen. A Pilot went to investors with his idea of
starting a shipping service that would send a package anywhere in the US
for $20.00 overnight. They laughed at him, "Who in their right mind would
pay $20.00 to send a package overnight somewhere". Eventually the Pilot
found someone to fund his ideas. The other investors are no longer laughing
now as the name of the Pilot's dream company is FedEx.
The bottom line is that if "magic" is going to happen regarding your ideas.
You will be the one to make them a reality. It all depends upon how
determined you are.
Hello.Thank you for your response, It really helped getting a grasp for this stuff. Just wanted to make sure I understand a few things. You can add transmitters, but you said you'd want them 2 miles apart from each other. So basically You can't just mount 4 or 5 transmitters at the home base? By spreading them out It then extends the range. Also, How big are these transmitters? and how difficult is it to gain permission to place them around the area?In regards to the automated equipment, Does this mean that you can go in and lay out the content you wish to have on the radio in advance? (so you're not sitting at the computer selecting each song All day long) Curious how far in advance you can program.Finally, I'm just curious if anyone does talk radio? through part 15 am? Can these stations become affiliated with radio shows? etc? I'm talking of Nation wide radio shows!Basically I have 3 areas i'm thinking of. Of course i'd only start with one and see how it goes. The first one is an Island, so I think as far as coverage I could get the most with fewer transmitters then the other areas. I was looking to play some talk radio shows, then have music during times also. Or complete talk, not quite sure. But would something like this work? under the part 15 am station??The reason why i ask all this is because in my area (not the island i talked about before) A guy has been cleared and still waiting approval from FCC for a low powered radio station. The market is completely open and he will do real well, my hopes was to have a good station to get some of the listener ship. Since he will get a lot of people turning on the AM dials.Again, thank you very much for sharing all your wisdom!regards,
Hi ???? -
I will try to answer your questions in the order they were received. Please try to
remember this before you get started. Getting a good sounding station on the
air is not easy. Anyone can set up a transmitter ... feed it audio ... and turn it
on ... and in most cases it will sound terrible ... especially on AM. My first feeble
attempts were pitiful ... so don't get discouraged (>:
TIR Stations (licensed) are different from Part15 AM stations. True TIR is 10
watts and yes you have to be a city, state, or local entity, in order to get licensed
for one. Most of the 10 watt TIR transmitters I have heard sound terrible. They
have big coverage areas though as there is no restriction on antenna type or
antenna height. In my opinion TIR stations are nothing more than AUDIBLE
SPAM. Did you know that you are not allowed to play music over a TIR station?
What irritates me the most about TIR stations is that they are overpowered. I
have heard the Burbank Airport TIR station up to 50 miles away. Hogging up
all that space to transmit meaningless *****. Their power output should be
cut down to 1 watt so that they can only be heard a few miles from the Airport.
Los Angeles is littered with allot of TIR stations ... in some cases they are on the
same frequency which really creates a mess. TIR is great for a service like you
want to provide ... but in a big city where the airwaves are already saturated it
So enough preaching .. let me answer your questions. I am not saying I have
all the answers so please accept my advice as advice you might want to take
into consideration with advice from others (>:
1. Do you know of any stations that operate with the same format? As i'm looking for other
creative content ideas for programming.
I personally don't know anyone that is operating Part15 TIR. There are allot of
resources available on the internet (lists of Part15 stations). Do a search on
google.com for "Part15 station list". Most of the info is complete with emails or
phone numbers regarding how to contact them.
2. the area i'm looking to get coverage is only about 2 or 3 miles. You mentioned you put two transmitters
close together and it boosted coverage and signal, however FCC doesn't really like that. Instead they like
transmitters 2 miles apart! Do you think 2 transmitters together would be alright? or are they talking about
like 4 or 5 together is not appropriate.
You can easily get that coverage area from a single transmitter if you are creative. The
main thing to remember about Part15 AM is that the FCC doesn't really give a *** about
it. You would have to really do something BIG to get busted. This would be something
like running a TON of power, foul language, pissing off your neighbors with religious
or political content. In my personal opinion your chances of getting busted even if you
were over powered would be almost nil. Don't try to hide from the FCC ... this is what
they hate the most. Before you put your station on the air write a short letter to the
enforcement division. Tell them who you are ... the technical details of your station ...
and why you are sure your installation is legal (send pictures). If they have a problem
with you they will contact you ... otherwise they know who you are. I did this before
I switched my station on the air ... I have been on 24/7 for (2) years and I have never
had a single visit from the FCC. I also told my local 1Kw AM Radio Station who I was
... what frequency I was on ... what type of station I had ... and why I was absolutely
sure I was legal. This keeps them from finding you by accident ... then assuming you
are a pirate ... then them filing a complaint against you. If the FCC receives a complaint
against you ... you WILL get a visit. Although it's not required it would always be best
to use a "FCC PART15" approved transmitter. Keep a copy of Part15 AM rules and
regulations with your station. The first thing the FCC will ask you is, "Do you have a
copy of the Part15 Rules and Regulations ... and do you understand them.
Sorry for getting on the soap box again ... let me answer your question:
A properly tuned mast mounted Part15 transmitter with a power output of 100mw
(mounted at roof level)(grounded) will only be loud and clear for about 1.4 mile. You
might be able to hear it for a mile but it will be so weak that you can't clearly hear the
In order to get your signal out further you need to take advantage in a loop hole that
was accidentally written into the Part15 rules and regulations:
"The antenna ... feedline ... and or ground cannot exceed 3 meters in total length".
If you mount your transmitter on a metal pipe ... ground the pipe ... then ground
your transmitter to the pipe ... is not the pipe your ground? What happens here is
that the pipe acts as the "other half of the dipole" and it will radiate. RF being AC
does not see the DC ground of the pipe. Negative currents will always find a way
to flow. The pipe being much longer than the CB whip on the transmitter will
cause the RF to radiate more from the "pipe" than the "whip". I call this, " running
the transmitter upside down. When you are transmitting at such a low frequency
the RF will always look for something longer to radiate from ... something that is
a multiple wavelength of the transmit frequency. Here is how to calculate what
a 1/2 wave antenna would be for 1610kc:
Formula: 468 divided by the (f) frequency in Mhz ... ie: 468/1.610 = 290.68 Feet.
(Calculates a 1/2 wavelength for a given frequency)
Divide 290.68 feet by (4) to get an "1/8th" of a wavelength = 72.67 Feet.
Divide again by (2) to get "1/16" of a wavelength = 36.33 Feet.
Mount your transmitter at the top of the 36' pipe. Ground the transmitter to the
pipe ... ground the base of the pipe to earth ground with a "copper" ground rod.
The easiest way to mount the pole would be by the side of a house securing the
bottom of the pipe to a concrete slab (ground rod nearby). The top of the first
section of the mast would be secured to the "eve" of the house with a bracket.
Don't use a stainless steel whip on the transmitter... this adds allot of weight. Use
a 96 inch "Francis" CB whip (fiberglass) ... light weight. Tune up the transmitter
at roof level and set the output to 100mw.
A transmitter set up in the above fashion should easily give you the coverage area
3.I need to do more research but i haven't found anything about how the content gets to the airwaves.
I would use a computer.. so are there hook ups where the computer connects into a transmitter receiver
type device? ALso, if someone wanted to use programming off an internet radio station. ( what i may do
in the off season for fun) Would you just point the transmitter programming device to the webpage? and
can this always be up and running.. or is it only running while the computer is turned on etc.
If your transmitter is at your home you would just run a shielded cable from the sound
card of your computer to the transmitter. You will need an "audio matching transformer"
between the computer and transmitter. The output impedance of the sound card is (8)
ohms and the input impedance of the transmitter will most likely be 600 ohms. If you
purchase a "AM1000 Rangemaster Transmitter from Keith Hamilton" he will include this
matching device with the transmitter.
Remember what I said about the "sound" of unprocessed audio on AM ... it will sound
like shit I assure you. If I were you I would pump my audio into some inexpensive
audio processors like:
1) Symetrix 422 (AGC, Leveler)
2) DBX 160x (Compressor, Limiter)
3) Inovonics 222 (single band AM audio processor, pre-emphasis, NRSC filter)
The above will cost you around $800. You will be surprised as to what a good sound
you will get out of them.
If your transmitter is remote you have several choices:
1) Part15 STL (Station Transmitter Link)
This requires a STL transmitter at your studio and an STL receiver at the transmitter
site. I have seen Part15 STL kits (minus antennas, feedlines) for sale on the internet
for under $200.00. You can process your audio at the studio before you send it to
the transmitter but I wouldn't go that way. To get the best sounding audio your
audio processing equipment should be at the transmitter site ... inline just before
2) Internet (TCP/IP) requires DSL internet connection (1.5meg down/256k up)
(DSL at studio and DSL at transmitter site)
You set up a "shoutcast" server at the studio (this requires a computer) and some
free software from "shoutcast.com". You set up a computer at the transmitter site
that will automatically connect to the URL of your shoutcast server when it is
powered on. If you loose power you need to set up the remote computer at the
transmitter site to recover from the outage. You pump the audio from the remote
computer at the transmitter site into your audio chain.
3) Broadcast Loop
Ask your local Phone Company about this. You feed the loop from your studio
then dial into the loop from the transmitter site. This would require a computer
that will automatically dial back up to your broadcast loop if the line should drop
out for any reason.
Any associated computers should be UPS battery backed up. Get the biggest
UPS you can get (30 minutes runtime).
In my opinion the absolute easiest and least expensive way to go would be Part15
STL. No computers, No internet service, Minimal power outage recovery worries.
I would still put a battery back up system at both the studio and transmitter sites.
I hope that this information helps you out. Remember that no matter what anyone
says or suggests ... you and you alone will stand tall before the FCC if you make a
mistake. Be careful and play by the rules and you will certainly have a lotta fun
with Part15 AM Radio.
The most important thing I could ever suggest to you is: "Part15 FM"? Don't do it
ever (>: Make a mistake there and the FCC will confiscate your equipment ... and
fine you $10,000.00. Your chances of getting caught 100%.
Good Luck (>:
Again, I appreciate your thoughts as I'm in the learning process of part15-Am. I just had a few quick questions. I have completely re-thought the programming I am looking to provide through Part-15 station. Once again my area that i'm looking to provide the station for is a small community of about 6,000 people. However, In the summertime (when I plan to run the station) approx. 4-5 million tourist.
I'm looking to use it as a (TIR) station. Which i've is said that is most commonly used format for part15 station. Basically i want it as a local tourist information radio. with history, events, ads talking about local hotels, restaurants, etc.
I'm hoping something like this can be done by a private person, instead of needing to be an organization/non profit. etc. my questions are;
1. Do you know of any stations that operate with the same format? As i'm looking for other creative content ideas for programming.
2. the area i'm looking to get coverage is only about 2 or 3 miles. You mentioned you put two transmitters close together and it boosted coverage and signal, however FCC doesn't really like that. Instead they like transmitters 2 miles apart! Do you think 2 transmitters together would be alright? or are they talking about like 4 or 5 together is not appropriate.
3.I need to do more research but i haven't found anything about how the content gets to the airwaves. I would use a computer.. so are there hook ups where the computer connects into a transmitter receiver type device? ALso, if someone wanted to use programming off an internet radio station. ( what i may do in the off season for fun) Would you just point the transmitter programming device to the webpage? and can this always be up and running.. or is it only running while the computer is turned on etc.
____A later e-mail_______
We also spoke about the Valor 160 Meter Mobile Antenna (which has been
discontinued by the way). My tests showed that a resonant antenna will increase
your signal strength 6db (1 s-unit). However you can't hear that small of a change
on a car radio (so what's the point of doing it).
I had excellent results with 2 transmitters 40 feet apart. I set the phase jumpers to
the default position on TX1. I put my field strength meter in the middle of the
transmitters then started moving the phase jumpers on TX2. I found a jumper setting
where my field strength doubled on the FS meter (in phase). This doubled my
coverage area. This test was run on the top of my patio roof (low level on tripods).
On a car radio I got a primary coverage area of 1 mile (loud full content). 2 to 3
miles secondary (full content but some objectionable noise). 4 miles extended (
50% content with objectionable noise).
I'd like to set up 3 transmitters as
1) -90 electrical degrees
2) 0 electrical degrees
3) 90 electrical degrees
All of them spaced 90 electrical degrees apart of course. You would set up the first
two then phase them till the signal strength doubled between them. You would then
get between 2 and 3 and set the phase jumpers on 3 until you doubled the FS again.
This should really work well. You should get 3 times the signal strength of a signal
transmitter in front of transmitter 3. Although I've never tried this, you might get an
"end fire" pattern both in front and to the rear of the transmitters.